From what people keep saying, Southampton sounds like an incredibly frustrating place to drive, but the phenomenon that Ziltro describes is not restricted to there.
Here in Reading, if you are going west along Queen's Road and wish to turn right at the arrow, it is almost always quicker to go straight ahead, do a U-turn and turn left instead. This is despite the fact that Queen's Road is only one-way before the arrow, and the road going north is also one-way (i.e. the junction is only of "two-roads-into-one" complexity).
Of course, any council road planner worth his salt will not only cause as much congestion as possible, but make it illegal or impossible to circumvent it (e.g. by putting up "no U-turn" signs). To that end, I doubt there are many examples of the phenomenon in London. You can see that the planners there spend a huge amount of time perfecting their anti-car measures. There's no escape...except not going to London in the first place.
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Paul Smith: a legend.
"The freedom provided by the motor vehicle is not universally applauded, however: there are those who resent the loss of state control over individual choice that the car represents. Such people rarely admit their prejudices openly; instead, they make false or exaggerated claims about the adverse effects of road transport in order to justify calls for higher taxation or restrictions on mobility." (
Conservative Way Forward:
Stop The War Against Drivers)